You can get a new lock and cylinder as a set from Out of Doors Mart. I just ordered one last week. The part # is 380341M. Be sure to read the description to make sure it is the one for your era of trailer, they have two different sets.
Keep me posted on your progress.

You are welcome. If you do order a new lock cylinder, be sure not to take the key out of the lock before you install it. It will damage the lock. There are instructions for replacing the cylinder on the Out Of Doors website.

Yes the part #'s should be the same. If you go to the web site where they show the exploded view and click on the blue square it will give you more info. Don't know what to tell you about the suspicious activity